Problem: Solve for $p$, $- \dfrac{5p - 10}{5p + 9} = 3$
Answer: Multiply both sides of the equation by $5p + 9$ $ -(5p - 10) = 3(5p + 9) $ $-5p + 10 = 15p + 27$ $10 = 20p + 27$ $-17 = 20p$ $20p = -17$ $p = -\dfrac{17}{20}$